Process and apparatus for concentrating ores



April 16, 1929. J.- F. NEWSOM 1,709,365

PROCESS Am) APPARATUS FOR CONCENTRATING ORES F ed Fe 7,1923 2Sheets-Sheet 1 PULPF 2a 5 1A OVERFLOvy 5 9 a. #A W BYMQI JL.

ATTORNEYS.

J. F. NEWSOM Filed Feb. 1923 2 Sheets-Sheet @J@ /1 TTORNEYS.

April 16, 1929.

PROCESS AND APPARATUS FOR CONCENTRATING CREE WIT Patented Apr. 16, 1929.i

UNITED STATES PATENT OFFICE.

oan rtnsnnn NEWSOM, or PALO ALTO, CALIFORNIA.

BROCESS AND APPARATUS FOR CON CENTRATIN G My invention relates to aconcentrating and classifying apparatus and process for ore bearingmaterial and as a preliminary step to remove the finerbarren sands andslimes from the material treated usually referred to as the pulp and toconcentrate the ore'into certain other coarser classes of sands whichare to be treated in subsequent ore dressing appliancesa The employmentof rectangular boxes, provided at the bottom with rows of hoppers ofvarying depths, for the purposes of settling out ore-bearing materialsaccording to their specific gravity has, I am aware,'been heretoforeresorted to, but such boxes hitherto employed have been used with veryslow currents and arranged for the settling out of slimes and theremoval of the excess water from the pulp, preparatory to furthertreatment of the slimes. In my invention, however, the box is employedWith a rapid current and is arranged for rejecting a large portion ofthe material passing to it, such rejected material being usually thefiner sizes only of worthless sands combined with the very fine siltsordinarily spoken of as slimcs.

I am aware that various types of shallow current classifiers commonlyknown as spitzkasten are employed for settling and ClflSSl fvin oreboarin materials into various sizes,

but these classifiers employ a shallow surface current with varyingsized pockets, in which the current is gradually slowed down and inorderto get as perfect a separation as possible employmentisnsuallyresorted to of a vertical current of water passing upwards through asettling'colunmi attached to the bottom of the Application filedFebruary 7, 1923, Serial 110,617,524, and in Federated Malay StatesNovember 30, 1922.

the length, width and depth of which is made 'in accordance with thequantity of material to be handled.

At the bottom of thisbox, rows of hoppers are provided with outlets orspigots in the bottom, through which the heavier materials, as they passthrough the box, are sorted out in accordance with their settling ratesin water.

The ore bearing material, carried in a current of water, and usuallyknown as the pulp is fed into one end of this box and that part of thepulp which is not caught by the hoppers escapes by an overflow outlet atthe far end of the box. In passing throughthe box the various gradesofcoarser sands and ore settle through the water, in accordance with theirfree settling rates in water, the coarser and heavier grams settlingnear the head of the box, the lighter and finer sands hoppers. In thetypeofclassifier which I am a now describing, namely'the spitz-kastcn,the material caught by the hoppers settles to the bottom of thosehoppers and into the settling columns and is there met by an ascendingcurrent and the materials that have a settling rate greater than thespeed of the ascending current scttlethrough the current and pass outthrough the spigot opening, but the materials which have a settling rateless than the speed of the ascending current are carried upwards, andmust be caught by the currents sweeping onwards through the hoppers andcarried over to the next compartment. These types of classifier havevery limited tonnage capacities when close work is done.

One of the main objects of my invention is to provide a concentratingapparatus, which settling into the hoppers nearer to the overflow endand the finest materials of all escaping by the overflow.

The process described above linings about the following result, namely,that the bulk oflhe ralmibleminerals, referred to herein as the ore.will he caught by con'iparatively few rows of the hoppers and infltheserows there will be also caught those portions of the barren materialwhich have'equalsettling rates with the ore grains, but since thevariation in size of the grains of the worthless material is usuallymuch greater in alluvial deof the hopper rows may be too low in grade towarrant subsequent treatment and may be 7 l of the material.

' In order to break up the return and eddy currents I provide aperforated plate or screen below the cellular feed above described andextending across the box. Through this plate, or screen a current offresh water, by

which is meant a current essentially tree from any ore-bearing material,enters the box from r a pressure box and is regulated in quantity andspeed at will and flows parallel to but below the pulp current.

This fresh water current passing into the box immediately below. thepulp current, coalesces with the pulp current and forms one even currentin the box and thus by preventingreturn and eddy currents permits the.variousmaterials brought into the box by the pulp current to settle tothe. bottom at their free settling rates and the entire surface area ofthe box is available for the continuous settling of the sands at theirproper rates; furthermore the ore and coarser sands as they settle tothe bottom of the box must settlethrough this fresh water current andthereby the cleanest possible separationis obtained.

While the ordinary type of feed sole may be used to convey the pulp intothe box and a fairly even flow imparted to the pulp. current Ihave'foundthat in order to impart the evenest possible flow to the pulpas it enters the box itis best to provide a pocket at the intake end'ofthe box (preferably with a deflecting vane) and a cellular feeddistributor. The vane is so placed that the rush oft-hepul tr current ischecked as'it enters the pocket and after passing the vane it enters thecellular feed, by means of which it is broken up intoniany separateindividual currents flowing parallel to one another, and as these issuefrom the cells heycoalesce and form one even current. t is obvious thatthe use or omission of the deflecting vane above described depends uponthe relative elevation of the pulp feed and the cellular distributor,and I do not make it an essential feature ofmy apparatus.

. In order to save headroom and floor space, to obtain'the greatestpossible elimination of barren material in; one appliance and toequalize so far as'po sible the supply of ore particles, the stream offleeting vane (2 bearing material going to the subsequent treatmentdevices, settlmg columns through which a vertical column of water passesmay be attached to the bottom of the apparatus above described and thuscombine in the one appliance two important steps of elimination by freesettling, followed by hindered settling, applied to the valuableportionsonly of the material resulting from the free settling process.

In order that the nature of my invention may be more readily understoodI refer to the drawings accompanying this specification.

In these drawings z- Fig. 1 is a longitudinal section through theclassifier showing the longitudinal arrange ment of the hoppers, of thefresh water supply, of the pulp feed, and of the cellular and pocketfeed control. d

Fig. 2 is a plan of Fig. 1.

i Fig. 3 is a section'on A A of Figs. 1 and :2 and shows a cross sectionthrough any particular spigot row.

Fig. 4 is a section on B B Fig. 1.

Fig. 5 is an enlarged section showing the arrangement of the feed pocketand the cellular feed apparatus.

Fig. 6 is a section on C C in Fig. 5.

Fig. 7 shows the arrangement withthe hoppers reinoved from Figs. 1, 2and 3 and with the settling column added forascending water current, butwith 4 longitudinal rows of settling spigots and troughs instead of 3 asin Figs. '1, 2 and 3.

Fig. 8 is aplan view of Fig. 7

Fig. 9 is a cross section of Fig. 7 on the line D D. 7

Fig. 10 isa detail of one of the settling columns shown in Figs. 7 and8.

Fig. 11 is a cross section of Fig. 10 on the line E E. r 1

Referring now in detail to the drawings, in which the same number isalways applied to the same part: Fig. 1, after the ore-bearing materialhas been sufliciently crushed and mixed'with water tofree the ore watercarrying the puddled, 1

ore is led in by the feed sole (1) to the feed pocket (2) in which theplunging and rushing current contingent upon a rapidly moving surfacecurrent is broken up by the de- From this feed pocket the pulp-bearingmaterial is led through the cellular feed distributor (3) which extendsacross the width of the box. In the present instance the top of thiscellular feed is shown approximately level with the surface of the Inorder to overcome water (4) in the box. any eddies and return currentsthat would be formed inthe box by the feed current, a fresh water supplyis brought through the pipe (5) into a pressure box (6) in which therapid current of the water in the pipe (5) is equalized, and fromwhichthe water .will enter, coalesce and sweep through the box, that thespeedand depth of the upper current carrying the oremay be controlled by thewidth and height of the cellular feed distributor (3), and in which thespeed and depth of the fresh water current may be'controlled by theamount brought in through the fresh water pipe (5) and. the height andlength of the perforated plate (7).

In order to produce an even steady current from the pulp feed to the boxas that material enters the box, the cellular feed distributor (3) is soconstructed that the length of the various cells through which the watermust pass is made greater than the width of each compartment or cell, asis indicated at (3) Fig. 5. By thisarrangement any boiling or plungingaction given to the water in the pocket (2) is overcome, and thecurrents flowing through the cells issue from those cells with parallelaxes, and coalesce into one solid even current in the box. As thecurrent, carrying the ore and sandsissues from (3) the solids carried byit will immediately begin to settle towards the bottom of the box inaccordance withtheir specific gravity and the sizes of their particles,the heavier and coarser materials settling out first, and thesuccessively finer and lighter materials settling last.

In order to remove both the settled out sands'and ore, hoppers (9) areprovided in the bottom of the box with spigot openings (10) at thehottomof the hoppers. These spigot openings are arranged in parallel rows bothlongitudinally and laterally and therefore classes of ore and worthlessmaterial of the same settling" rates will be caught in the same lateralrow of hoppers, that is to say, the hopper rows (9)-vvith their spigots(10) which are successively further from the feed intake. will eachcarry slower and slower settling classes of material, but each row willcarry material of approximately the same sorts both as regards sizes andas regards ore contained. In practically all cases 'iiralluvial andother near surface deposits, the larger percentage of the ore will becaught in the spigot rows which lie nearest to the feed end of the box,and successively smaller portions of the valuable material. will becaught in the rows further removed from the intake end, thisdistribution being largely controllable by the quantity of the freshwater supplied tothe box through (7) and by the height of the cellularfeed distributor (3). It becomes possible, therefore, to so regulatethese elements that the maximum portion of the valuable material may becaught in the narrowest possible zone lying across the box, to conveythis high grade materialto subsequent treatment appliances suitable fortreating the sizes and classes of material coming from it, and todiscard the material that passes through the remaining spigot rowswithout further treatment, and thus the largest pos sible discard ofbarren materials may be reached without overloading subsequent treatmentdevices.

In order to provide against the clogging of the cellular feed (3) byroots, twigs, and other extraneous .zmaterials, the feed distributor ismade reversible and is pivotally mounted (11), so that it may bereversed from time to time by the hand wheel (12) or by any automaticdevice that might be made to operate at stated intervals.

In order to make water-tight joints at the top and bottom of thedistributor, and not to interfere with turning it, pliable fins (13) areattached to the distributor, which will impinge on the verticalpartition (14) at the top of the distributor and (15) at the bottom ofthe feed pocket (2) and a similar fin of pliable material is attached tothe inner side of the partition (15) at the bottom of the feed pockets(2). By means of these fins, the feed distributor (3) can be reversedfrom time to timeas desired and the joints between the feed distributorpartitions (13 and 14) remain essentially water-tight. Any roots, twigsor other extraneous material which might have collected on the intake ofthe distributor will be immediately. Washed out by the current when thedistributor isreversed, and this material will be carried through thebox, and out by way of the overflow opening 17). In order to preventcurrents passing into the box around its ends, short semi-circular vanes(16) extend out from each side of the box and practically contact withthe ends of the feed distributor. The dog (12) with spring attachedholds the feed distributor in correct working position when once set. i

iVood fibre, grass and other. materials which are so small, or whosespecific gravity is solow that they will not settle and be caught by thehoppers within the time the water travels from the intake end to theout: flow end of the box, will pass out at the overflow point (17). Bythis arrangement the fine sands, the woody fibre, vegetable matter andthe bulk of the clayey material fed to the box are discarded at the samelevel at which they are brought to it.

Under certain conditions itis advisable-to get a further elimination ofworthless material in the preliminary settling and discarding step thancancbe obtained by the free settling action alone, and it isadvantageousto accomplish this result in a single machine in order to save the headroom and floor space that would be required in employing separatemachines. The discard of additional barren material over thatobtained bythe free settlingprocessmay be obtained by emllO - lower end of thesorting column.

ployment of the hindered settling rate of material of dilierent sizesand specific gravities settling in water.

Referring now'to Figures 7, 8 and 9, Fig.

'2' shows a longitudinal section of the double current classifierequipped with hindered settling columns. In this apparatus theconstruction issimilar to that shown in Figs. 1 and 2, except that thedividing partitions oi which a few are indicated by the number (19 whichform the square hoppers in Figs. 1, 2 and 3 are omitted, thus makinglongitudinal troughs (19') through the box. These troughs are separatedfrom each other by the angular partitions (21) at the bottom of thesetroughs, as close together as practicable, are settling columns of whicha few are indicated by the number (22) with fresh water supplied to themthrough the water main (23), and individual pipes (24). At the bottom ofthese columns is an opening (25) through which the settled sand, ore anda portion of the water supply escape.

The fresh water supply through the main (23) is introduced underpredetermined pressure and of requisite amount, and the quantity ofwater supplied to each settling column (22) is greater in amount thanthe quantity of water that escapes through the spigot openings (25).Thus an upward current of water is produced in the sorting columns (22)and through this upward current of water the sand and ore particles mustfall. These particles whose settling velocity is less than the speed ofthe upward current through the column will be carried up by that currentand carried on to the next settling column. By regulating the watersupply to the succeeding columns (22) so that there are slower ascendingcurrents in the succeeding rows ofcolumns a close sorting action isobtained.

When the supply of sands to the settling column is small .so that thegrains falling through each column are widely separated from each other,the free settling rate will come into play in the columns and but littleelimination of barren material will result in this arrangementbeyondthat already ob tained by the double horizontal currents in the upperpart of the box. But when the sand supply is larger so that the sandgrains coming to each column are close together the hindered settlingratio of sorting will come into play, and the quantity of barrenmaterial eliminated will be great.

Fig. 10 shows an enlarged section of the 11 is a cross-section on F-F ofFig. 10 and shows the way in which the water supply, (24:) is led intothe column. At the lower end of the sorting column (22) there may beinserteda funnel shaped, perforated plate orscreen (27)"attached to thetube (26). The object of this screen is to cause theeven distribution ofwater supply coming in at (24') as that supply passes into the settlingcolumn (22). For equalizing the flow of water through the screen (27) awatercompartment (26) is provided into which the water from (24) is led;between the walls (29) of this compartment and tube (26-) is an annularopening (30) through which sands and other extraneous material enteringthe compartment may escape, and. by regulating the sizeof this opening,the down ward flow of sand and water through (26) may be controlled.

No novelty is claimed for these settling colums as illustrated inFigures10 and 11 as regards assembly or principles involved as.

these columns are w ll known and used appliances. The novelty of myapparatus lies in the combination of these settling columns with aboxsettler as described.

By means of this arrangement, I combine in one machinetheiollowingsteps. (I) The classifying and eliminating capacities of thedmible current box classifier by mean s of which a large portion ofbarren material coming to the machine is at onoediscarded, thusrelieving the succeeding appliance from treating t is worthlessmaterial, and (II) A second treatmentotthevaluebearing material, (whichhas been alreadygreatly reduced in bulk) by means of ascending currentsof water and these currents operating in combination with the doublehorizontal current classifier, to which they are attached, have theproperty of automatically becoming hindered settling columns, when thesupply of sand is great and, therefore whenthe largest possibleelimination of barren material is required, and of free settling columnswhen the supply of sand is small. It is obvious, therefore, that thiscombination of appliances will bring about an automatic adjustment andregulation of I the materials assin throu h the a 3 liance and passingon to succeeding treatment machines. That is to say, when the proportionof coarse sands in the feed coming to the double current box settler (8)is large, so that the discard of fine material in that settler would besmall, and the treatment machines following the settler would for thatreason be overcrowded with material fed to them, then the hinderedsettling principles of sorting will come into playin the settlingcolumns (22), there will be a correspondingly larger elimination of thebarren sands in this part of the machine, and thereby the averagequantity of feed goingto the succeeding treatment machines will beequalized, while practically the total ore content will be caught inboth cases.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed I declare thatwhat I claim is 1. An ore classifier comprising a boX adaptedto befilled with liquid and means for feeding a currentof water carryingslimes and coarse material into the liquid in a horizontally movingunagitated stream, below the surface of the liquid, whereby the coarsematerial settles through the liquid solely by gravity.

2. An ore classifier comprising a box adapted to be filled with liquid,a pulp feed receptaclo at one end of the box, a port connecting thereceptacle with the box below the level of the liquid therein and meansin the port for causing liquid from the pulp teed receptacle to enterthe box in a substantially solid unagitated horizontal stream.

3. An ore classifier comprising a box adapted to be filled with liquid,means for introducing a deep horizontal stream of water into the box, afeed receptacle above said means adapted to receive water carryingslimes and coarse material and means for introducing said water carryingslimes and coarse material into the liquid in a smooth flowinghorizontal stream above and in the same direction as the water streamand below the surface of the liquid in the tank, whereby the coarsematerial settles through the liquid solely by gravit it. An oreclassifier comprising a box adapted to be filled with liquid,classifying chambers in the bottom of the box, means for introducing ahorizontal stream of water into the box, and a cellular feed distributorarranged above-said means and adapted to introduce an unagitated s reamof water carrying slimes and coarse material horizontally into theliquid above the water stream.

5. An ore classifier comprising a box adapted to be filled with liquid,classifying chambers in the bottom of the box, means for introducing ahorizontal stream of water into the box, a pulp feed chamber, a cellularfeed distributor connecting the pulp feed chamher with the box and abattle wall in said chamber to check the rush of the entering current. i

6. An ore classifier comprising a box adapted to be filled with liquidand from which liquid overflows, a plurality of hoppers forming thebottom of the box, the hoppers being arranged in series in the directionof the length of the box, means for introducing a nether current ofwater into the box above said hoppers and means for introducing acurrent of water carrying slimes and coarse material into the liquid ina horizontally moving, unagitated stream below the surface of the liquidand above and in the same direction as the nether stream, whereby thecoarse material settles through the liquid solely by gravity.

7. The process o'f'classitying ore which comprises flowing a current ofsubstantially clear water horizontally through a box filled with water,and bringing a horizontal current of water containing ore slimes andcoarse ore-bearing material into the box below the level off the watertherein, and above the clear water current, and in the same direction asthe clear water current, so that the two currents merge and passhorizontally and quiescently through the box, and so that the coarserore-bearing material in the upper current setties solely by gravity tothe bottom of the box through the clear water current 'at differentlocations, due to the settling rates in water of the solid particles,and the slimes pass out over the overflow.

In testimony whereof I hereunto set my hand this 4th day of December,1922.

JOHN FLESHER NEVVSOM.'

